diff --git a/types/gapi.people/index.d.ts b/types/gapi.people/index.d.ts
index d39dc0b875..550316d192 100644
--- a/types/gapi.people/index.d.ts
+++ b/types/gapi.people/index.d.ts
@@ -133,6 +133,15 @@ declare namespace gapi.client.people {
   }
 
   interface Birthday {
+    metadata: FieldMetadata;
+    date: Date;
+    text: string;
+  }
+
+  interface Date {
+    day: number;
+    month: number;
+    year: number;
   }
 
   interface Event {